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Enhancing the detection of early listening effort Hearing impairment is often diagnosed decades after individuals start experiencing substantial effort when trying to understand speech in noisy situations. As such, this listening effort may be a promising early indicator of hearing impairment. However, it is not currently captured by standard hearing tests. Dr. Björn Herrmann, Baycrest's Canada Research Chair in Auditory Aging and Scientist at the Rotman Research Institute (RRI), aims to address this gap with an important grant from the Canadian Institutes for Health Research (CIHR). He and his colleagues, including collaborator Dr. Jennifer Ryan (Senior Scientist), are studying how eye movements change as listening effort increases, and how this relationship changes in older adulthood. Based on this knowledge, they will develop an innovative method to assess listening effort using eye movements, leading to better outcomes for individuals living with hearing impairment. Enhancing older adults' speech comprehension Senior Scientist Dr. Bernhard Ross and his team at the RRI are using magnetic resonance imaging (MRI) and magnetoencephalography (MEG) to study the relationships between hearing loss, brain aging, and understanding speech in noisy situations. They have found that reduced levels of the neurotransmitter GABA – an important chemical messenger in the brain – lead to an imbalance in individuals' brain waves. This imbalance impairs the brain's ability to combine speech sounds into meaningful words, in turn making it more difficult to understand speech in noisy situations. Based on these findings, the team has developed a new computer-based training program to help older participants with different levels of hearing loss improve their understanding of speech in noise. Using musical training to maintain the ability to understand speech in noisy environments In a recent study, Senior Scientist Dr. Claude Alain and his team found that playing a musical instrument can help older adults maintain their ability to understand speech in noisy conditions. The researchers used MRI to compare the brain activity of older musicians, older non-musicians, and younger non-musicians while they were asked to identify different sounds masked by noise. They found that the older musicians performed as well as the younger non-musicians and had similar brain activity during this task, with comparable regions of the brain being engaged. In contrast, the older non-musicians showed very different brain activity. This suggests that musical training helps the brain sustain its ability to identify speech in noise as we age. This knowledge could lead to the development of novel training methods to help older adults preserve their ability to listen in noisy conditions. Aging and Brain Research Feature: Hearing and Music Many older adults develop hearing loss as they age, which negatively impacts their crucial ability to isolate relevant sounds from background noise in day-to-day communication – for example, following a friend's conversation in a noisy restaurant. Hearing loss not only puts them at risk for social isolation, but also increases their chances of developing dementia. Foundational research at the Baycrest Academy aims to better understand the relationship between speech comprehension and cognitive impairment, and to use this knowledge to improve older adults' lives. 10 BAYCREST ACADEMY FOR RESEARCH AND EDUCATION

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